A carry-on bag that appeared to contain bomb components -- but in reality had nothing out of the ordinary -- prompted an evacuation of about 1,000 people at San Francisco International Airport on Sunday, officials said.

At 12:48 p.m. a baggage screener near Gate E at Terminal 3, which serves mostly American Airlines, alerted a supervisor after seeing that a bag contained what appeared to be components for a bomb, according to police and airport spokesman Mike McCarron.

Within seven minutes police deemed that "there were items, articles inside the carry-on luggage that did resemble components of a possible explosive device," said San Francisco police Lt. Bill Darr.

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Two men and a woman from South Carolina, who had been trying to board a connecting flight to Dallas, were detained and questioned by police and the FBI -- but gave answers that were unsatisfactory, leading authorities to order an evacuation, police said.

After the area was cleared, a bomb squad blasted the carry-on bag with a water cannon at about 4:25 p.m.

By about 5 p.m., passengers were allowed back into the terminal. They walked right by the remains of the bag.

The three passengers who had been detained were released by police around 6 p.m. and allowed to board their flight.

Police did not say what they found in the bag that had resembled a bomb. A man who appeared to be the owner of the carry-on bag was fishing through its strewn contents and collecting the remaining items in white plastic bags. A janitor swept up what was left behind.

The frustrated and nervous passengers, some of whose flights were delayed for hours, were still confused at 5:45 p.m. about when the planes would take off and what had happened.

"My husband called American Airlines from New York, and they told him that my flight had already taken off," said Anne Gruppo of Larchmont, N.Y., who was traveling with her 18-year-old daughter, Erica. The two were separated for three hours when the daughter went to get some food at around the same time the suspicious package was found. Using cell phones, they located each other, but they were separated by a police line.

"I had to pay a taxi $9 to get from the departure area to the arrival area to reach my mom because they wouldn't let me down the stairs," said the daughter. They caught a 10 p.m. flight to New York.